African trypanosomes escape the host immune system by periodically changing their Variable Surface Glycoproteins (VSGs). In T. equiperdum this is done in an ordered manner. The VSG genes are activated by a process of duplicative transposition of silent basic copy genes. Those genes expressed early in the infection have complete basic copy genes while those expressed late are composite genes made by the duplication of at least three basic copy genes all of which are pseudogenes. We wish to examine the molecular mechanisms by which the late genes are constructed and which determine their ordered expression. We also wish to examine the regulation of VSG gene transcription in complex expression sites as well as the mechanism of general transcription in these organisms. Finally, we propose methods for the development of a transformation system for these organisms.